Detector-locking for power-interlocking systems



W.-K. HOWE. DETECTOR LOOKING FOR- OWER INTERLOCKING SYSTEMS.

APPLICATION FILED MAY15, 1919. 11,399,257.

Patented/Dec. 6, 1921.

:rfi.

UNITED STATES PATENT OFFICE,

WINTHROP K. HOWE, OF ROCHESTER, NEW YORK, ASSIGNOR TO GENERAL RAILWAYSIGNAL COMPANY, OF ROCHESTER, NEVJ YORK, A CORPORATION OF NEW YORK.

DETECTOR-LOCKING FOR POWE-RJNTERLOCKING SYSTEMS.

Specification of Letters Patent.

Patented Dec. 6, 1921.

Application filed May 15, 1919. Serial No. 297,344.

To all 10760772, it may concern Be it known that I, lVIN'rHRoP K. Hown,a citizen of the United States, and resident of the city of Rochester,in the county of Monroe and State of New York, have invented a new anduseful Improvement in Detector-Locking for Power-Interlocking Systems,of which the following is a specification.

This invention relates to power interlocking systems for railroads, andmore particularly to a system of detector looking for preventing thethrowing of switches under trains.

It is essential that some provision should be made in power interlockingsystems so that a switch may not be thrown under a train or directly infront of it. This may be accomplished in one way by breaking theoperating or controlling circuits for the switch machine, or switch andlock move ment, through contacts of a track relay, or a repeater relay,controlled by the usual detector track circuit associated with theswitch, so that when a train enters or stands upon this detector trackcircuit, the switch cannot be thrown. lVith such an arrangement,however, it may happen that the train will enter the detector trackcircuit just at the time the switch is being operated, with the resultthat the switch may be left unlocked or in mid-stroke by reason of thefact that the entrance of such train instantly stops the operation ofthe switch machine. Such a thing happening might be extremely unsafe anddangerous; and under such circumstances it would be better to have theswitch complete its movement, if it has started to operate, rather thanhave it unlocked or in mid-stroke.

In view of these considerations, one ol ject of this invention is todevise a simple arrangement of circuits and controlling devices suchthat the operation of the track relay of the detector track circuit iscoordinated with the operation of the switch machine in such a way thatthe dropping of the track relay will prevent the switch machine beingoperated, if it'is at that time in either the normal or reverseposition, but will not prevent the switch machine completing itsoperation, if such operation had commenced before the track relaydropped.

Other detail features and advantages of the invention will appear morefully hereinafter, and the novel features of the invention will bepointed out in the appended claims.

In describing my invention reference will be made to the accompanyingdrawing, which illustrates in a simplified and diagrammatic manner theparts and circuits associated with a switch machine and its controllinglever, together with the devices and circuits constituting my improvedsystem of detector locking.

In disclosing my invention, I have illustrated it applied to a wellknown system of electric interlocking, such as disclosed, for eXample,in my prior Patent 1,288,595, dated December 24, 1918. The constructionof the switch machine and the manner of its operation from a lever inthe tower, together with the various circuit controllers and operatingcircuits, are fully explained in my prior patent; and consequently, itwill be suiiicient for a clear understanding of the present invention toexplain the general scheme of operation of those parts directlassociated with the improvement constitut ing my present invention. Forconvenience the parts and circuits shown on the accompanying drawinghave been given the same reference characters used on the drawing of myprior patent, so that by referring to said patent the operation of theentire system may be readily understood.

The switch S associated with the switch machine S. M. is indicatedconventionally; and in a similar manner I have illustrated the usualdetector trackcircuit, comprising the track battery 4: and track relayT. In the particular arrangement shown, the track relay T controls therepeater relay It; but this is optional. As explained in my prior patentabove mentioned, the circuit controller of the switch machine includes acontact block 55, which is moved mechanically from its existing extremeposition to its midde or intermediate position during the initialunlocking movement of the switch machine, and which remains in thatposition until the switch machine has completed its cycle of operationand is again fully locked, whereupon said contact block will beautomatically shifted to its other extreme position.

This contact block 55 of the switch machine is provided with anadditional contact piece 6, which is arranged to bridge or electricallyconnect contact fingers 7 and 8, when said contact block is in themiddle position.

The front contacts of the relay R are included in the main common returnconnection 104t104 of the switch machine. When the contact block 55 isin the middle or intermediate position, these front contacts of therelay R are shunted by conducting path comprising conductor 9, contactspring 7, contact piece 6, contact spring 8, and conductor 10. Thus,before operating current can be supplied to the switch machine, it isnecssary to ave either: (1) the relay R energized, or, (2) the switchmachine at an intermediate point in its cycle of operation.

The operatlon of my system of detector locking will be readily apparentto those skilled in the art with only a brief explanation. lVith thevarious parts in the normal position, as shown on the accompanyindrawing, a train entering the detector trac circuit for the switch Swill shunt out track relay T and deenergize relay R. The switch machinebeing in the normal position, the denergization of relay R breaks thecom mon return connection 104104, so that as long as the train remainson the detector track circuit, power cannot be supplied to the switchmachine to operate the switch, Suppose, however, that the towermanstarts the switch machine into operation just at the time a train entersthe detector track circuit. Under these conditions, power would not becut off from the switch machine, since the main common connection wouldbe established through the contact springs 7-8 and contact piece 6.Consequently, in spite of de'energization of relay R by the entrance ofthe train into the detector track circuit, the switch machine would beable to complete its cycle of operation.

In describing my invention, I have selected a simple form and have shownits application to one type of power interlocking. It willbe evident,however, to one skilled in the art that the same features and principlesof operation characterizing my invention can be applied to other powerinterlocking systems, and may also be used in conjunction with thevarious well known features commonly employed in interlocking systems,

which have not been disclosed, I wish it to be understood, therefore,that the embodiment of my invention herein shown and described is merelyillustrative and does not exhaust the various modifications andadaptations of the broad idea of means underlying my invention.

What I claim as new and desire to secure by Letters Patent, is

1. In a power interlocking system, a! detector track circuit, a switchmachine, means controlled by said track circuit for preventing operationof the switch machine while said track circuit is occupied, and meansgoverned in accordance with the operation of the switch machine forrendering said first mentioned means ineffective while the switchmachine is operating.

2. In a power interlocking system, a detector track circuit including atrack relay, a switch machine having its operating circuits carriedthrough front contacts of said track relay, and means for shunting saidcontacts while the switch machine is operating. 1

3. In a power interlocking system, a detector track circuit including atrack relay, an electrical operable switch machine having a main commoncarried through front contacts of said track relay, a circuit controllerclosed while the switch machine is at any intermediate point in itscycle of operation and open when such cycle of operation has been fullycompleted to throw the switch points to either position, and a shunt forsaid front contacts governed by said circuit controller. 4. In a powerinterlocking system, a detector track circuit, a switch operatingmechanism, a circuit controlling said mech anism and governed by thetrack circuit, and means for maintaining the continuity of said circuitindependently of the track circuit control while the mechanism isoperating.

5. In a power interlocking system, a switch operating mechanism, a trackcircuit, means controlled by the track circuit for preventingapplication of V power to the mechanism while the track circuit isoccupied, and means for permitting the mecha nism to complete a cycle ofoperation once started prior to the entrance of a train into the trackcircuit.

' 6. In a railway trai'iic controlling system, a track including a trackcircuit, asw'itch, an electrically controlled mechanism for said switch,a circuit controlling said mechanism, a plurality of means forcontrolling said circuit, one of said means controlled by said trackcircuit, and means for maintaining the controlling circuit'of saidmechanism throughout its operation independently of said track circuitcontrol.

7. In a railway trailiic controlling system, a track provided with atrack circuit, a track switch, an electrically controlled mechanism foroperating said switch, means for controlling said mechanism by saidtrack circuit, and means for removing said control when said mechanismis operating.

-8. In a tratlic controlling system, a track provided with a trackcircuit, a track switch, a power operated switch machine, a controlcircuit for governing'the operation of said machine, a relay controlledby the track circuit and acting to interrupt said control circuit whenthe track circuit is occupied, and means fo preventing the effectiveaction of the relay while the switch machine is operating.

9. In a power interlocking system, a switch operating mechanism, a trackcircuit, and means at the switch acting to prevent operation of themechanism while at rest in an operated position when the track circuitis occupied, said means permitting the mechanism to complete anoperation once started regardless of the entrance of a train into thetrack circuit in the meantime.

10. In a power interlocking system, an electrically operable switchengine, a detector track circuit, a circuit controller governing theapplication of operating current to the switch machine, means foropening the circuit controller when the track circuit is occupied, andmeans efiective only when the switch machine is operating to supplyoperating current thereto independently of the track circuit control.

11. In a power interlocking system, a switch operating mechanism, meansfor at times preventing operation of said mecha nism, and automaticmeans effective while the mechanism is operating to nullify theinfluence of the first mentioned means.

12. In a power interlocking system, an electrically controlled switchoperating mechanism, a track circuit, a control circuit for saidmechanism which is interrupted while the track circuit is occupied, andmeans for independently maintaining the continuity of the controlcircuit while the mechanism is operating.

13. In a power interlocking system, an electrically controlled switchoperating mechanism, a control circuit therefor, a relay at themechanism acting when deenergized to interrupt the control circuit, atrack circuit, means controlled by the track circuit for governing therelay, and means for shunting the contacts of the said relay while theswitch machine is operating.

14. In a power interlocking system, an electrically operable switchmachine having a common wire, a track circuit, a circuit controller insaid common wire governed by the track circuit, and means forestablishing a shunt around the circuit controller while the switchmachine is operating.

15. In a power interlocking system, a switch operating mechanism, asource of current and control means for governing the operation of saidmechanism from a distant point, a track circuit, and means preventingoperation of the mechanism while the track circuit is occupied, saidmeans permitting the mechanism to complete a cycle of operation oncestarted regardless of the entrance of a train into the track circuit inthe meantime.

16. In a power interlocking system, a switch operating mechanism, trackcircuit controlled means for governing the operation of said mechanism,and means dependent upon the movement or" the mechanism. to permit it tocomplete a cycle of operation regardless of the control of th trackcircuit control.

17. In a power interlocking system, a switch operating mechanism,circuit controlling means closed while the mechanism'is operating andopened when the mechanism has completed a cycle of operation, and trackcircuit controlled means cooperating with the circuit controlling meansto govern the application of power to the mechanism and thereby preventoperation thereof from either extreme position while the track circuitis occupied but permittingcompletion of a cycle of operation startedprior to the entrance of a train into the track circuit.

18. In a power interlocking system, a track switch, mechanism foroperating the switch, a track circuit, and means controlled by the trackcircuit for preventing operation of the mechanism from either of itsextreme positions but permitting the mechanism to assume either extremeposition if operating when the track circuit becomes occupied.

19. In a power interlocking system, a switch operating mechanism havingan operating circuit, and track circuit controlled means located at theswitch for governing the operation of the mechanism, said means beingeffective only when the mechanism has fully operated to one or the otherof its extreme positions.

20. In a power interlocking system, a switch operating mechanism, atrack circuit, means preventing operation of the mecha nism while thetrack circuit is occupied, and means whereby the mechanism may beopera-ted to either of its extreme positions if it is operating at thetime the track circuit becomes occupied.

21. In a power interlocking system, a track switch, electricallycontrolled mechanism for actuating the switch, a track circuit, andcircuit controlling means partly governed by the track circuit andpartly in accordance with the condition of said mechanism 'forpreventing operation of the mech anism from rest while the track circuitis occupied but permitting the mechanism to complete a cycle ofoperation started prior to the entrance of a train into the trackcircuit.

22. In a power interlocking system, the combination with a trackcircuit, of switch operating mechanism having its operation from eitherextreme position dependent on the mitting operation andindication of themachine if it is operating at the time the track circuit becomesoccupied. a

p 24. In a power mterlocking system, a switch machine, means actuated bythe switch machine when it changes from either extreme operatedposition, and track circuit controlled means cooperating with said meansto govern the operation of the switch machine. a

25. In a detector locking arrangement for switch machines of the typewhich have a 7 locking plunger, a contact block operated by the plungerand shifted to the middle p0sition and t0 anextremeposition when theplunger is unlocked and locked respectively, a contact piece carried bysaid block, and contact fingers cooperating with said contact piece,said fingers being electrically connected while the contact block is inits middle position and disconnected when the block is in either extremeposition.

WINTHROP K. HOWE.

